Reduction of GHG emissions by geological storage of CO₂: Anatomy of the Heartland Aquifer Redwater Carbon Capture and Geological Storage Project (HARP), Alberta, Canada

The purpose of this paper is to identify and characterize a geological storage site at more than 800 m depth that is capable of storing large quantities of carbon dioxide (CO₂) in the Alberta Basin and is close to a large CO₂ supply.

Five criteria are used to select the site: total volume of the pore space of the formation for CO₂ (i.e. capacity); accessibility of the pore space in the storage site to CO₂ (i.e. permeability or injectivity); ability of the storage site to retain the CO₂ once the CO₂ has been injected (i.e. containment); protection of other resources from contamination; and cost of the whole process: capture of the CO₂, transport and storage (i.e. economics).

The Heartland Redwater Leduc Reef is identified as a site that has large capacity, good injectivity, and is an excellent trap. Contamination of the oil in the oil reservoir at the top of the reef (the third largest oil reservoir in Canada) is avoided by co‐optimizing CO₂ storage and oil production.

The Heartland Redwater Leduc Reef is ideally located at relatively shallow depth (1,000‐1,200 m), has a large amount of residual oil and is close to large CO₂ sources which make it one of the most economically attractive sites in the Western Canadian Sedimentary Basin.

The Heartland Redwater Leduc Reef Saline Aquifer CO₂ Capture and Geological Storage Project (HARP) is investigating the technical and economic feasibility of injecting significant volumes of CO₂ into the large water‐saturated portion of a huge Devonian reef that is capped by a comparatively small oil reservoir, nevertheless the third largest oil pool in Canada. The reef has a total areal extent of nearly 600 km³, is more than 1,000 m deep and is up to 275 m thick. Based on the high‐water injectivity in the reef, the potential exists to inject sustainably in excess of 1,000 tonnes of CO₂ per day per well in the aquifer portion of the reef. Preliminary storage capacity estimates for the aquifer are in the order of one gigatonne of CO₂. The Heartland Redwater Leduc Reef has the combination of a large oil reservoir sitting on top of a much larger local aquifer. This is a unique site for storage in Canada and could be a model for the rest of the world for carbon dioxide capture and storage.